Does A Fish Tank Need An Air Pump? How Can You Tell?

If you’re putting together a new aquarium, you may have heard of something called an “air pump”. What is it, and does a fish tank need an air pump?

An air pump isn’t always necessary, but we’ll cover the scenarios where an air pump would be helpful.

What Is An Air Pump?

An air pump is exactly what it sounds like — it pumps air into your aquarium! It’s a small machine that sits outside of the aquarium — you don’t want to get it wet.

You’ll attach plastic tubing to the air pump for the air to travel through. The opposite end of the air pump attaches to a piece of equipment like a sponge filter or a bubbler. The filter or bubbler, of course, does go inside the water.

As the air pump pushes air through the tubing, it creates bubbles. The bubbles create more flow in your tank. They also provide your tank with more oxygen.

Why Are Air Pumps Useful?

The main reason people use air pumps is to add oxygen to the water. But, they provide other uses as well.

Air Pumps Add Oxygen To The Water

Some sources will tell you that bubblers don’t really add oxygen to the water. They believe this because the bubbles pop at the surface.

But, the bubbles popping at the surface are actually what helps add oxygen to the water!

Gas exchange happens at the surface of the water. Carbon dioxide (CO2) leaves the water while oxygen enters it. But, it’s difficult for gas exchange to occur when there is no flow in the tank. This is why stagnant water has less oxygen than water with plenty of flow.

Adding a bubbler to your tank increases surface agitation in your tank. This allows for better oxygen intake.

Sometimes, a filter creates enough surface agitation that you don’t need a bubbler. But, for larger aquariums, a bubbler is often necessary.

They Add Extra Flow

Some fish need more flow than others, so it can be helpful to add a bubbler to your tank.

For example, danios are native to southern Asia. They live in freshwater streams where the currents are strong. So, they like to have lots of flowing water to play in. A bubbler, and even a powerhead, can be helpful with this.

They’re Good For Medicating

Many medications form a film at the water surface which prevents gas exchange. Bubblers will ensure that the medication mixes, preventing the film from developing. It also helps to evenly distribute the medications throughout the tank.

They’re Great For Sponge Filters

A popular type of filter is a sponge filter. They provide excellent biological, chemical, and mechanical filtration. At the same time, they create bubbles that oxygenate your tank.

With other kinds of filters, you have to buy a separate bubbler to add to your tank. Sponge filters create their own bubbles. So, they eliminate the need for extra equipment.

They Make Good Decorations

Most people want their aquarium to look pleasing, so they don’t like the thought of adding an “eyesore” to the tank. Luckily, there are many lovely bubblers that will spruce up your tank.

Some bubblers hide in the back of the aquarium and produce colored lights that look pretty at night. Some attach to props to make your tank fun. There is a bubbler that pushes air through a volcano with red lights to look like an eruption. There are also little diver figurines that blow bubbles out of their mouths.

How Do You Know If Your Tank Needs An Air Pump?

It’s not necessary for every tank to have an air pump. So, how do you know if you need one?

If Your Fish Are Gasping For Air

The easiest way to tell if your aquarium needs more oxygen is by watching your fish. If the tank doesn’t have enough oxygen, you’ll often see your fish at the surface of the aquarium gulping for air.

Know Your Fish’s Preferred Environment

As we mentioned above, some fish prefer flowing water over stagnant water. It depends on the species, and you need to do what’s best for your fish. This means doing your research before buying anything.

For example, betta fish are weak swimmers who don’t do well with flow. Combine that with the fact that they usually live in small tanks, and a bubbler usually isn’t the best choice.

But, fish that need lots of oxygen or flow will appreciate a bubbler. Here are some fish that love air pumps:

You Have A Warm-Water Aquarium

Warm water naturally contains less oxygen than colder water. So, you’re more likely to need a bubbler in a warm-water tank.

Don’t Use An Air Pump If You Add CO2 To Your Tank

Some aquatic plants need CO2 supplements. As we explained above, surface agitation causes more CO2 to leave the water. So, if you’re using CO2 supplements, you’ll want to avoid air pumps and bubblers.


You need so much different equipment to set up a nice aquarium for your fish. At times, it can be overwhelming.

Fortunately, air pumps are one of those things that aren’t necessary for every aquarium. But, if you need a better current or more oxygen in the tank, they are a wonderful asset.

Don't forget to check out